In optical systems using fiber optics for transmitting signals by light energy, it is often necessary to couple two fibers end-to-end for the signal transmission path. The optical fibers are of very small diameter and are of fragile construction. Typically, an optical fiber cable comprises an optical fiber covered by a jacket of plastic material for protecting the fiber from damage due to handling during installation and exposure in its operating environment. A typical single filament cable comprises a glass fiber having a diameter of a few thousands of an inch and a protective jacket having a diameter of a few hundreds of an inch. In order to minimize the coupling losses at the interface of the two optical fibers, the ends of the fibers must be accurately aligned.
A connector for optical fiber cables must provide for accurate alignment of the fibers being joined. Additionally, the connector should provide support for the cable jacket in order to relieve the fiber itself from stress for so-called strain relief. A most difficult problem in optical fiber connectors has been that of providing simple and effective terminations or contacts for the fibers which facilitate repeated connection and disconnection from each other and which afford accurate alignment of the fibers upon reconnection.
In the prior art, pairs of single filament optical fiber cables are coupled in end-to-end relationship by attaching a ferrule to the end of each fiber and mechanically aligning and connecting the ferrules together. Typically, in this prior art, the fiber is encased in the ferrule so that the end of the fiber is flush with the end of the ferrule. Two fibers are coupled by placing the respective ferrules in end-to-end abutting relationship. This type of connector is disclosed in U.S. Pat. No. 4,087,158 granted to Lewis et al. and U.S. Pat. No. 4,090,778 granted to Phillips et al.
Also in the prior art, attempts have been made to provide an optical fiber cable connector in which a termination supports a cable with a free end of the fiber extending therefrom. The free ends of corresponding pairs of optical fibers are disposed in a V-groove on one of the terminations and a holding means on the other termination bears against the fibers to hold them in alignment. This kind of arrangement is disclosed in U.S. Pat. No. 3,885,859 granted to Dalgleish et al. and in U.S. Pat. No. 4,088,386 granted to Hawk.
A general object of this invention is to provide an optical fiber cable connector with terminals which overcome certain disadvantages of the prior art.